ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Mar 2026
Jan 2026
Latest Journal Issues
Nuclear Science and Engineering
April 2026
Nuclear Technology
February 2026
Fusion Science and Technology
Latest News
U.K. vision for fusion
The U.K. government has announced a series of initiatives to progress fusion to commercialization, laid out in a fusion strategy policy paper published March 16. A New Energy Revolution: The UK’s Plan for Delivering Fusion Energy begins to describe how the government’s £2.5 billion (about $3.4 billion) investment in fusion research and development over five years will be allocated.
Nam Zin Cho, Jaejun Lee
Nuclear Science and Engineering | Volume 159 | Number 3 | July 2008 | Pages 229-241
Technical Paper | doi.org/10.13182/NSE159-229
Articles are hosted by Taylor and Francis Online.
A coarse-mesh nodal method in cylindrical (r, ,z) geometry, e.g., of pebble bed reactors, based on the analytic function expansion nodal (AFEN) methodology, is described in this paper. Two unique features are (a) no use of transverse integration - allowing a nodal scheme in (r, ,z) geometry - and (b) nodal solution expressed in terms of analytic basis functions - leading to high accuracy and readily available reconstruction of homogeneous flux distributions. Additional features of multigroup formulation, two methods of void region treatment, and coarse-group-rebalance acceleration are implemented in the TOPS code and tested on several benchmark problems, including the Organisation for Economic Co-operation and Development/Nuclear Energy Agency PBMR-400 Benchmark Problem. The TOPS results are in excellent agreement with those of the VENTURE code, using significantly less computer time.